Experimental investigation of wing tip vortex

Particle image velocimetery was used in a low-speed wind tunnel to investigate and characterize wing tip vortex structures. A rectangular wing of a SWIM model was used as a vortex generator in two different configurations, (i) plain wing and (ii) flapped wing with trailing edge flap extended at 20 degrees. Vortex flow quantities and their dependence on angle of attack at a chord base Reynolds Number of 32.8x103 and 43.8x103 were evaluated. Assessment of measured data reveals that the peak values of tangential velocities, vortex strength and vorticities are directly proportional to the angle of attack. The vortex core radius value grows slowly as the angle of attack is increased. Both plain and flapped configurations showed similar trends. The peak tangential velocities and circulation distribution doubled when the flapped configuration was used instead of the plain wing

Experimental investigation of plain- and flapped-wing tip vortices

Particle image velocimetry was used in a low-speed wind tunnel to investigate and characterize wing tip vortex structures. A rectangular wing of a subsonic wall interference model was used as a vortex generator in two different configurations: 1) plain wing and 2) flapped wing with the trailing-edge flap extended at 20 degrees. Vortex flow quantities and their dependence on angle of attack at Reynolds numbers of 32:8 � 103 and 43:8 � 103 were evaluated. Assessment of measured data reveals that the peak values of tangential velocities, vortex strength, and vorticities are directly proportional to the angle of attack. The vortex core radius value grows slowly as the angle of attack is increased. Both plain and flapped configurations showed similar trends. The peak tangential velocities and circulation almost doubled when the flapped configuration was used instead of the plain wing

Study of Dynamic Interaction Between Low Re Aerodynamic Load and Flexible-Biomimetic Wings with Tailorable Stiffness by FSI Modeling

In the present work, we investigate dynamic interaction and response of flexible bio-inspired morphing wing structure to a low Reynolds aerodynamic load. The aspects of inspiration are as follows. First, the segmentation of the wing into rigid and flexible segments. Considering a leading edge constitution of bone and muscle. In addition to a flexible trailing edge composed of feathers. Second, the material properties provided by experimental biology in literature are adopted such as the bending stiffness and Young's modulus. The development of numerical models allowing non uniform distribution of properties are developed and implemented into an OpenFoam finite volume solver that couples fluid dynamics to a structural solid dynamics solver through the FSI interface. In the course of this work, the validation is performed for a NACA6409 airfoil considering a rigid segment of 40\% and flexible segment 60\% chord length in order to test the aero-structure behavior for an aerodynamic load of air flow at low Reynolds number of $\boldsymbol{5\times 10^5}$ for the fluid and feather inspired material properties. The results suggest that bio-inspired techniques can be reproduced in engineering configurations.Comment: This is the author's version of an article that has been published at 2023 AIAA SciTech Forum - 23-27 January 2023. The final version of record is available at: \url{https://arc.aiaa.org/doi/abs/10.2514/6.2023-0826

Mental Health State Classification Using Facial Emotion Recognition and Detection

Analyzing and understanding emotion can help in various aspects, such as realizing one’s attitude, behavior, etc. By understanding one’s emotions, one's mental health state can be calculated, which can help in the medical field by classifying whether one is mentally stable or not. Facial Recognition is one of the many fields of computer vision that utilizes convolutional networks or Conv Nets to perform, train, and learn. Conv Nets and other machine learning algorithms have evolved to adapt better to larger datasets. One of the advancements in Conv Nets and machines is the introduction of various Conv architectures like VGGNet. Thus, this study will present a mental health state classification approach based on facial emotion recognition. The methodology comprises several interconnected components, including preprocessing, feature extraction using Principal Component Analysis (PCA) and VGGNet, and classification using Support Vector Machines (SVM) and Multilayer Perceptron (MLP). The FER2013 dataset tests multiple models’ performances, and the best model is employed in the mental health state classification. The best model, which combines Visual Geometry Group Network (VGGNet) feature extraction with SVM classification, achieved an accuracy of 66%, demonstrating the effectiveness of the proposed methodology. By leveraging facial emotion recognition and machine learning techniques, the study aims to develop an effective method

Chemical composition and antimicrobial activity of essential oil of wild and cultivated Origanum syriacum plants grown in Sinai, Egypt

The main constituents of essential oil (EO) of Origanum syriacum L. collected from cultivated and growing wild in Sinai, Egypt were identified and determined by GC-MS. The antimicrobial activity of these essential oils against Gram positive and Gram negative bacterial strains was studied. The antimycotic activity of these EOs was also evaluated against eight fungal strains isolated from different sources. Forty-six compounds were identified in the EO of both samples, dominated by carvacrol in cultivated type. Thymol, gamma-terpinene, linalool and 4-terpineol were the most represented constituents in O. syriacum plants collected from wild populations. Both EOs showed antibacterial activity with varying magnitudes, while EO from cultivated O. syriacum showed high antibacterial activity against Staphylococcus aureus with an inhibition zone of 32 +/- 4.0 mm. Both EOs showed good antifungal activity against all fungal strains. O. syriacum EO from cultivated plants showed the lowest MIC 0.25 mg/L with Aspergillus fumigates clinical strain isolated either with Aspergillus flavus

Low Reynolds number effect on CFD prediction of bio inspired aerodynamics

This work is motivated by the need for the implementation of the best numerical modelsfor low Reynolds flows and presents the state–of–the–art of the implemented models for thetransition of the laminar-turbulent predictions. The numerical models are applied to investigatethe aerodynamic characteristics and flow behavior around bird–like airfoils. Two DimensionalReynolds Averaged Navier Stokes (2D RANS) and Three-Dimensional Unsteady (3D U-RANS)methods are applied at a Reynolds number of105, whereas two-dimensional laminar simulationsand three-dimensional Large Eddy Simulation are employed for the known Owl-like airfoil atReynolds number of2.3×104. The numerical results of flow fields around Owl-like airfoil atthe latter Reynolds number using two-dimensional laminar and 3DLES predict correctly theunsteadiness of the aerodynamic coefficients. The 2D and 3D RANS methods are predicting wellthe aerodynamics characteristics for the man-made-bird-like airfoil at Reynolds number of105

Association Between Hemoglobin A1C and the Severity of Acute Ischemic Stroke in Sudanese Patients in Omdurman Military Hospital

Background: Hemoglobin A1C (HbA1c) levels are known to be linked to a higher risk of stroke. However, no research data is available on the impact of HbA1C on the severity of acute ischemic stroke in Sudan. Methods: This study is a descriptive, cross-sectional hospital-based study of 40 cases of acute ischemic stroke. Ischemic stroke was confirmed using computed tomography (CT) scan at admission; all subjects’ blood HbA1C levels were also measured. Participants were divided into two subgroups based on HbA1C at admission, good glycemic control (GGC) (<7 HbA1C) and poor glycemic control (PGC) (>7 HbA1C), and neurological impairment was assessed using the National Institutes of Health Stroke Scale (NIHSS). Results: The age distribution of the participants was 45-85 years, with an average age of 63.5±9.2 years with the highest frequency (67.5%) in the age group of 55-75 years. PGC had a statistically significant high HbA1C value of 8.9±1.3 (P=0.000), when compared to GGC subgroups 5.1±0. The association between stroke severity and HbA1C levels on admission in this study was statistically significant (P value=0.005), on admission (78.6%) PGC had moderate to severe stroke (> 18.8 NIHSS) versus (33.3%) that of the GGC (>10.4NIHSS). The frequency of elevated HbA1C levels in patients with acute ischemic stroke was 70% in this study. Conclusion: PGC was shown to be linked to the occurrence of stroke and to its severity

Shisha smokers’ determinants of use, knowledge and perception towards shisha (waterpipe) smoking in Penang, Malaysia

Background: Tobacco smoking is a serious health problem worldwide. Malaysia as many of south Asian countries faces the challenge of rising tobacco consumption. Despite the apparent spread of Shisha smoking phenomenon among Malaysian population, little is known about the safety concerns and determinants of Shisha smokers in this community. Objectives: This study aimed to determine the social determinants of Shisha smoking among Malaysian population in Penang Island, Malaysia and to explore their health related knowledge and perception toward Shisha smoking. Methods: The survey was conducted using simple random sampling by randomly distributing self-administered questionnaires to consumers in Shisha lounges located in Penang Island. Statistical analyses were performed using the Statistical Package for Social Science (SPSS) version 20. Results: A total number of 171 (42.75%) of respondents participated in this study. Mean age was 21.5±4.4 years. The majority were male, Malay (79.6%, 63.1% respectively). About 97.1% of respondents smoke Shisha either alone or with tobacco cigarettes. The majority (63.1%) started Shisha smoking at an age ≤ 20 years old, always in a café' (72.2%), share Shisha smoking with others (81.6%). Only 35.9% of respondents reported smoking Shisha daily. 71% reported smoking ≤ 7 bowls per week. 50.5% claimed smoking Shisha for more than 60 minutes per session. Boredom, outing and meeting with friends and family ranked first among the motives for smoking Shisha. Regarding knowledge about Shisha smoking, the majority believes that cigarettes are more harmful, more addictive and has more nicotine than waterpipe (60.2%, 71.8% and 67%; respectively). A large proportion (66%) of respondents believes that Shisha smoking doesn't transmit hepatitis infection. The majority of respondents perceived Shisha smoking acceptable by society and parents, compared to cigarettes (67% and 60.2%; respectively). The vast majority of respondents believe that Shisha smoking relieves stress and tension (77.7%), while the minority believes that Shisha smokers have more friends than non-smokers. Regarding access to Shisha, half of respondents agreed that Shisha is easily accessible than cigarettes. The majority of respondent foresees increasing popularity of Shisha smoking in the next 5 years (83.5%). Conclusion: This study showed that there is a high prevalence of Shisha smoking among the Malaysian youth associated with false believes about its health effects. Further studies involving larger population are encouraged

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication